The present invention relates to burners for gaseous fuel and particularly burners of the type employed for cooking appliances such as cooktop arrangements where a plurality of burners are disposed on top of a cabinet for cooking food in receptacles. The invention relates particularly to household cooktop burners where a plurality of burners are supplied from a manifold connected to a source of fuel gas with individual user operated control valves for regulating the flow of gaseous fuel to the individual burners.
Heretofore, it has been commonplace to have a plurality of cooktop burners on a domestic gas range arranged in an array with the individual burners having an annular or generally ring-shaped configuration with the flame generating ports disposed in peripherally spaced relationship to provide a ring of discrete flames emanating from the burner ports. It is known to provide such a burner with a base having a tubular inlet portion and an enlarged diameter end flange for defining a plenum or air fuel mixing cavity which is closed by a burner cap. The flame-generating ports in such a known burner design are formed in the outer annular rim of the base cavity, such that when the cap is in place gaseous fuel flowing into the tubular inlet is mixed with air typically by an inlet aspirator and is discharged through the burner ports for flame generation. Such known burners employing a base and cap have formed the flame-generating ports extending radially through the outer rim of the base which are closed by the cap to form flame-generating ports.
Heretofore such cooktop burners for mass production of domestic ranges have also employed cast metal burner bodies with flame ports drilled therethrough which has proven to be quite costly in high-volume production.
However, it has been found that the circular configuration of the drill port burner provides improved flame-generating performance and is more desirable in this aspect than a burner having grooves formed in the base which are closed by the burner cap.
In such an aforesaid cooktop burner arrangement, when sudden drafts or rapid fluctuations in the flow of fuel and air such as might be caused by debris or foreign matter in the fuel line or variations in supply pressure, the flame may be extinguished in some of the flame-generating ports and remain in others. Where the burner valve has been turned by the user to a position for very low flow, the small flames generated at the ports of the burner may be insufficient in width to reignite the gaseous fuel mixture emanating from the adjacent ports when flame has been extinguished therefrom. Thus it has been desired to provide a cooktop gaseous fuel burner which has a stable flame at varying fuel flow rates and has the ability to reignite flame at adjacent ports when the flame has been extinguished in some but not all the burner ports and which is capable of high volume mass production at low manufacturing cost.